72 Duster 340 Pistol Grip Linkage

Hi all. Just purchased a 72 Duster with the factory 340 and the A833 4 speed transmission. The previous owner converted the shifter to the pistol grip shifter. I believe it was done correctly but to do some troubleshooting i'm trying to familiarize myself with this modification.

If i were going to start over and do a fresh install of this pistol grip, what parts and linkages would i use with the A833?

Thanks,

Paul